風扇輔助空調環境之舒適度研究

A Study of Thermal Comfort in the Fan Assisted Air Conditioned Environment

廖健瑋(Jian-Wei Laio)

指導教授 ： 簡良翰

國立臺北科技大學/機電學院/能源與冷凍空調工程系碩士班/碩士(2011年)

https://doi.org/10.6841/NTUT.2011.00185

摘要

本研究主旨探討風扇應用於空調節能之舒適度研究，模擬採用九種風扇位置進行舒適度分析，並配合舒適度問卷調查與溫濕度、風速實測。模擬顯示之人體表面溫度，其中風扇吹送之位置以頭部及背部較為涼爽，腹部次之。本研究考量到人體受風之感受，故避免風扇吹至頭部而造成不舒適，因此，在問卷調查及實驗時採用吹送腹部的方式進行。在舒適度實驗中，以風速及溫度為控制條件，進行人體舒適度之問卷調查，問卷之溫度範圍23.9~28.1℃，濕度範圍60~73.5%，風速各別為0.1m/s、2.18 m/s、2.36 m/s及2.54 m/s。
本研究模擬結果顯示：在衣著量為0.5 clo、代謝率為1.2 met（坐著工作）、輻射溫度為28℃、濕度為70%及室內乾球溫度28℃時，未置入風扇與置入風扇之模擬PMV值分別為1.18、1.08，而計算之PPD值各為38%及30%，屬於一個悶熱狀態，也顯示置入輔助風扇後達到降低PMV值之效益有限；模擬並顯示風扇位置的改變對環境之PMV影響不大。但本研究透過問卷調查得知，此環境參數下之人員滿意度卻高達90%，尤其是置入風扇(2.18m/s、2.36m/s、2.54m/s)後，因風量上升使受測者對舒適溫度得以提高；由此可知模擬所得之PMV值對置入風扇後之人體舒適度預測有較大之誤差。經由本舒適度問卷與實驗之回歸分析所得之舒適度經驗式可預測置入輔助風扇之舒適度，其最大誤差值為 0.53以內，而此經驗式預測人員滿意度百分比之最大誤差值±17%。套用本研究之結果，控制空調設備在28℃且搭配風扇使用後，相較於26℃已達節能12%，雖使用風扇會導致額外之耗電量，相較於冷氣耗電量電扇耗電量屬於少量，故預測此種方法節能至少可達10%。

關鍵字

舒適度風扇 ； 空調節能

並列摘要

In this study, thermal comfort of fan assisted air-conditioned room have been investigated numerically, and compared with the survey of the thermal comfort questionnaire in measured temperature and wind speed. Nine kinds of fan locations were simulated. The simulation shows that the skin temperature of the body is the coolest when the fan is blowing towards head or back, and second by blowing towards abdomen. To prevent discomfort causing by blowing towards human head, the questionnaire are conducted by blowing towards the abdomen. In the comfortable test, with wind speed and temperature are control parameters. The temperature ranged from 23.9 to 28.1℃,and humidity varied from 60 to 73.5%. The temperature has been divided to three zones,and tested with wind speed 0.1 m/s, 2.18 m/s, 2.36 m/s and 2.54 m/s for each temperature zone.
The simulation shows that the PMV values were 1.18、1.08 without fan and with fan, respectively under the condition of: the amount of clothing 0.5 clo, the metabolic rate of 1.2 met (sedentary), the radiant temperature is 28℃, humidity of 70% and indoor dry-bulb temperature 28℃. The PPD value calculate is 38% without fan,and 30% with fan. These results indicate that both, enviroments are hot and the fan has limited influence on thermal comfort. The simulation also shows that the fan location has negligible influence on the environment PMV. However, the questionnaire survey in this study shows that the satisfaction of thermal comfort was as high as 90% under the same environment of the simulation especially for the fan speed at 2.18 m/s, 2.36 m/s, 2.54 m/s. The thermal comfort increased with increasing air flow rate. Hence, the PMV simulation yields considerable error for the case having a fan in the air-conditioned space. By regression analysis of the questionnaire in thermal comfort experiments, an empirical correlation was obtained. The correlation predicted the comfort index with a maximum uncertainty of 0.53, and it predicted satisfaction percentage with a maximum uncertainty of ±17%. By applying the results of this study, the air-conditioning unit can be set at 28℃ with a fan. Compared with a setting of 26℃, approximately 12% electric power can be saved. Although the use of fans may result in extra power consumption, power consumption of fans is relatively small as compared with the air-conditioning power consumption. Hence, this method is expected to save at least 10% of electricity.

並列關鍵字

Thermal comfort ； Fan ； PMV ； Air velocity ； Energy saving

參考文獻

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